Traveling stoker-grate.



P. WL HEDDEN.

TRAVELING STOKBR GRATE.

` APPLIUATION FILED sBPT.21,1909.` RENBWBD MAY 4, 1911. 1,010,758.

2 SHEETS-SHEET 2.

Patented Dec. 5, 1911.

l JA/z/ UNITED sTATEs PATENT oEEioE.

FRANK W. HEDDEN. OF JERSEY CITY, NEW JERSEY.

.-T all whom it may concern.-

Be it known that I, FRANK VILMARTH HEBBEN, a citizen of the United States of America, residing at Jersey City.y inthe county of Hudson and State of New Jersey, have invented certa-in` new 'and useful Improvements in Traveling Stoker-Grates, of which the following is a specification.

-This invention relates to mechanical stokers for automatically firing steam boi-ler or other furnaces.

The invention has for its object to provide improved air-seals at'rear portions ofl i the traveling. grate wit-hout using parts liableto quicklybiun out and 'Qwithout e1n- 5 ploying ashes or other unreliable friable nial terial'as an air-sealing medium; and to fuel-carriers and prevent clogging or jamming ofthe grate by hard clinkers on said 5 fuel which sifts through Vdraft openings of the grate; and to lprovide a simple and efiicient system of draft regulating damper's at the grate ash-zone.

The vinvention will rst be; described and part of this speciicatioii, Figure 1 is a of' the grate bar web. Fig. 7 is an enlarged centrally broken-out transverse vertical section on the line a-ain Fig. l. Fig. 8 is a sectional side view of the rear grate turn omitting the inner drum and with a for- Wardly arranged fiat cuter abutment. Fig.

9 is a centrally broken-,out sectional side" view showing front and rear turns of a modified grate. Fig. 10 shows the rear grate turn of Fig. 9, without an inner air-sealiiig `drum. Fig. 1l shows how an independently7 movable air-sealing drum may be used beltween diskwheels supporting the rear grate turn. Fig. 12 shows arnoditiedlongi'tudnal A,

TRAVEELING STOKER-GRATE.

)Specication of Letters Patent.

Application led September 21, 1909. Serial No. 518,761. Renewed May 4, 1911. Serial No. 625,084.

Patented Dec. 5', 191i.

link-grate and ash-zone damper's; Fig. 13

shows a link-grate having inner fuel-siftings conveyers, and F ig; 14 is a perspective view of a few assembled links yused n Figl. f ff Referring now .,moreespeciallv tov Figs. 1 to 6 ofthe drawings. the numeral 1 indicates the front turn of the endless grate, 2

is the upper grate run,3 isthe rear grate turn, and 4 is the lower grate run. It now is preferred to use fuel-carriers formed as transverse grate. bars having a main imperforate or air-excluding -web portion 5 provided with outer longitudinally projecting teeth' or fingers 6 which loosely intermesh with teeth of adjoining bars to form a' draftproviding fuel bed at the upper grate' run. provide for grindingsoft clinkers from the Each grate fbar web 'comprises the part 5, aridan inner iniperforate vmovable part which is preferably made as a plate .7 coupled by hinges 8 to the main web portion 5.

The transverse grate bars are preferably coupled together. This is done b txforming or providing a fixed longitudinal lug 10 on each end of two steel plates k9, 9 which form i front and rear portions ofthe inner part of the vmain bar web 5. The two lugs 1 0. 10 at then will be specied in the appended'claiins. In theI accompanying drawings forming I each end of the web oppose anbuter link 11,

and between the parts 10.-11, are placed the en ds of links 12. 12. All parts 10. 11, 12, are pivoted together b v removable bolts` or pins 1 3, as shown 'in Fig. 4. The `spaces 14, between the ends of theflinks 12. receive the teeth of front and rearsp'rocketwheels 15, 16, respectively mounted on transverse shafts 17. 1S. supported in the ,stoker side frames 19. 19. Tliese'frames Carr;r rollers 20, sustaining the upper and lower grate y' runs 2, 4. The front shaft 17 is journaled in movable boxes 21, operated by screws 22, for taking up undue slackness of the endless grate. The grate inav be operated b v ordinary worm-wheel and ratchet gearing 23. or bv any other mechanism.

The Stoker front is adjustable vvertically with a hopper 24. and mav be supported bv bolts 25. orotherwise. to regulate the depth of fuel fed fi'om the hopper 'upon theupper grate. run 2, under they ignition arch 26;

Therear portion of the grate is supported bythe sprocket wheels 16, and'also an outer air-sealing and clinker-'grinding abutmentwhich mav be thetopfofalow-"wall y V27, built across the furnacebutis preferablv a metal block ori capf28ff'fiied tfsaid'walL This Wall may af pulling this opened to,v allow ashes which had fallen from the 'rea-r grate turnB, to flow from a rear ash-pit 33, formed between the wall 27,' and Va higher vwall l34, into the front ash-*pity 35.

i v be described.' With these' fuel carriers' This pit 35, andthev spaceorvchamber 36,

betweenr the up er and lower grate runs `2,'

4, form -the-air-int'ake, and the hot products pass through the main combustion chamber 37, and 'around or 'through asteam -boiler 38, or other structure set above or nearV the grate. i. i Y

To prevent passageofY air from the air-in- ;take 35-36, into ithe combustion chamber 37, exceptas'needed for maintaining proper combustion of fuel 'on the upper graterunl 2, it isnecessary to .provide both inner and outer air-sealingmeans or devices atrear parts of the traveling grate.- The improved air-'sealing means constitute. important fea- 4 tures of this invention and are adapted to.

.runs 2, 4, to there form Vthe most effective grates having fuel carriers made with either movable or immovable inner portions. The

air 'sea-ling means as applied toa'n' `endless grate having transverse fuel caf-riers formed with' inner movable web parts 7, willfirst 5-4'6-7, there is preferably used within the rear grate turn 3, a' transverse drum 39, shown corrugated and fastened; to flanges 40 on the vixmer 'faces' of the iopposite sprocket-wheels `16, 16.' As the gratebars form the rear grate turn 3, the drum 39, acting as a' guide, folds the movable web i parts '7 ontheirhinges 8, as at 7-2, in Figs.

1 and 2, and edge portionsof the parts 7-2 then abutror closely approach each other, and said parts 7-2 also abut the inner edges of the web parts o.- 3 thus is air-sealed from within or atthe inside by Vedgewise contact ofy inner parts 7 -2 'of adjoining grate bars. Each web part 72 also has two. lines of air-sealing contact with two parallel ridges'of 4the corrugated drum 39, thus further assuring an effective air-seal at the inside of the grate turn 3. Each grate bar v567, thus-'preferably has four air-sealing places, two with adjoining bars and two with the; drum; 'The drum corrugations also provide pockets- 41 4 receiving. fine ashes which thuscannot- 'pre- -v vent. effective air-sealing adjustment'at'7e-2,

of the movable web parts 7. drum 39 be omitted the inner air-seal atthe grate turnB would be made by the grate bar parts 7 when adjusted'as at` 7-2, by inner flange guides .42 onI the sprocket wheels 16,

as shown in Fig. 8 of the drawings. The

outer abutment 28 spans the Vspace4 between 1 the, main imperforate webfpa1ts'5-0f any two adjoining grate bars and thus Vcoacts with said parts 5 and the inner imperforate grate bar web, parts 7, when closed M1792,

Arod ,the `door may attimes be;

The .grate turn l Should the l to completely air-seal the inside and outside of rear parts ofthe grate. n The web hinges 8 are specially designed to allow the web part 7 to turn' the angular cornerrof the main -w par-t5, 4or-its plate 9, and to laterffold closely against theinner edge of the part 5 to then prevent-passage of air-between said` parts 5,-,l T hehinges 8 comprise one member 43'fixed-to-the4 a'rt 5 or its plate 9 and having' lugs-44;lprov1jded with vertical 'slots'.45."A These slotsreceive f the ends of a pin 46 which is` fixed in a lu 47 on 4the-'other hinge member 48y fastene to the web part 7. .'The' main web part-5,

or 154-9, is notched to 'receivev the lhinge "lugs and to permit'risingofv the pin-carrying lug 47 as. the folding web part-7 lsettles snugly against'- the inner edge-of the'main web part-5 while the pin -ends rise in the-lug slots 45l f The, hinged webparts preferably-have 1 sufiicient width ,when folded to fully close 'dge-to-edge at-'theupper and-lower grate draftr dampers and lfuel siftings` conveyers hereinafter described. A This causes' the edge portion of one web p'art 7 to slightly overlap the edge of the adjoining part-7 while they at 7-2, travel' together around the'rear grate turn 8 to internally air-seal it by edge phrase .edgewise contact includes this slight preferred 'edge' overlapping of the web parts 7 at therear grate turn, well asa true edge-to-edgecontact which there would occur if t-he parts 7 were made nar-A rower and then wouldnot tightly close edge'wise at the upper and lower grate runs.

The out-er abutment 28 may be located directly under the rearl grate turn 3,V 'as then has a concave face fitting a portion of sai-dturn 3.- The'outer abutment also may have'a fla-t top and thenwould be located forward of the` grate turn' 3, as shown/at bar web parts 7 at the lower grate run di wise lcontact as abovej described. This ,105 shown in Figs: 1 and 2,and 9 to 13,-and` 284-1, in` Fig.' 8.? When-the Aconc'ave '-ab'utrectly in front/ofthe rear. grateturn to;

thereform aninner air-seal or barrier..

4Lower guides coact with the grate bar web parts 7- for various purposes. Theseguides preferably comprise two o r Amore longitudinal bars 49- fixed' at their longer front portions A49-3, to overlying brackets .50` which f are vfastened to the opposite sideframes 19. -Theupwardly yielding rearv parts ofthe Abars-49 comprise intermediate Jl'iigher-level V portions 49--2, and extreme rear-.portions` 49-.1, which arey at the. same' lower level-as the front guide -parts 4943. Brackets" 51 fixed to the frames 19, have ends which, underlie the guide bars 49 at the points of junction of their parts 49 1, 49-2. The guide bars normally rest upon said brackets 51, and may rise therefrom.

As the closed grate bar web parts 7 2, pass forward from the air-'sealed rear grate turn 3, they run under the guide bar ends 9 1, which hold ,them closed edgewise as at 7 3, to convey ashes falling from the drum at the turn 3, until said closed parts 7 3, pass along under the higher guide' bar partsf19-2, which permit said closed parts 7 3, to' tilt open as at 7 4, vand discharge the ashes into the front ash-pit 35. As 'the opened web parts 7 4, move forward under the guide bar parts Hl19-3, they are again automatically closed edgewise as at 7 5,

, and then serve as conveyers which 'carry toash-zone dampers.

ward the'furnace front practically all of the tine good fuel 52 which sifts through draft openings of the front portion of the upper grate run 2. These fuel siftings 52 thus are conveyedforward until the closed web parts 7 5, pass the front ends'of the guide-bars 19, when Vsaid .web parts successively and` fully tilt open downward as at 7 6, and discharge the fuel siftings into a chamber formed bet-weenthe teeth 6 and web parts-5 7, of two adjoining gratel bars. Arsv these bars begin their front .turn at 1 aroundV the sprocket wheels .15, the narrow` sihuous openings 54 which appeared at the lower grate run L1between the teeth 6 of adjoining bars'become much larger openings 55 around the diverging bar teeth, as shown in Figs. 2 and 3, and the fuel sift-ings 52 in the chamber 53, gravitally escape through said enlarged openings 55, as shown at 52 1, in Fig. 2', and fall outside the furnace front and'later will be re-charged into the fuel feeding hopper 24. the movable grate bar web parts 7,1nay be permitted to open at 7 1, live being so shown in Fig. 1,'three yin Fig. 2, and two in Fig. S. i l

In view of varying depths of fuel on the upper grate run 42, and of varying speeds of travel ofthe grate, and of varying draft pressures maintaining combustion of fuel on the grate, it is desirable and sometimes necessary to provide adjustable air-barriers or dampers at or below the rear part or ashzone of said upper grate run. Mechanical stokers have hertofore had various types of It is new to use inner movable grate bar web parts 7 as such dampers vand to close them bv subjacent Apivoted frames two or more o f which may be used. Two frames 56, 57, are shown and they are pivoted together by the shaft 5S on the front frame 57, while the rear frame 56 fixed to the stoker side ,frames 19. Any approved mechanism maybe used to'successively raise the pivoted frames 56, 57 such as rods 61,62, coupled to crank-arms 63, 64,

Any desired number ofl fixed to the frame pivot shafts 59, 58. When the rear frame 56 is raised about level by pulling the rod 61, said frame will'be locked suitably, say by a pin 65, passed through the rod into a side frame 19. All grate bar web parts 7, passing over saidraised frame 56, will be closed edge-to-edge as at 7 1, in Figs. 2 andS, to serve as dampers cutting 0H' air draft through all that ortion of the grate ash-zone overlying sai parts 7 1, while webparts 7 overlying the front still lowered frame 57 will remain open, as in Fig. 2. Should larger closed damper area be required this maybe obtained by pulling. the rod 62, thereby turning lthe shaft 58 and raising the front -frame 57 which then will he locked to cause closure as atl 7 1, of all pivoted weh parts 7 moving over said frame.

By unlocking and retracting the rods 62, 61, I

web damper plates 7 1, to again. gravit-ally .-open," as shown in Fig l. The lowered frames rest upon cross-bars or other stops 66, which are ifxed to the Stoker side frames 19, and hold the lowered frames clear above .the moving lower grate run 4. The swinging dan'iper-plates actuated by the pivoted frames thus cutoH passage of airv through any desired deiinite area of the grate ashzone .andthereby avoid the'bad effects of open blow-holes ,at lthinner rear portions of the iieon the grate. Should three frames be used to assure still larger ash-zone damper area, ,the third fralne would be pivoted to the front end of the frame 57 and would have its 'own pull-rodconnections for raising it after the -two frames4 56, 57- were raised, thus closing more -web parts 7 at 7 1, substantially as above described.

From the above description it will be obvious that inner lmovable or hinged grate bar parts or plates 7. are, automatically closed at. 7 1. for anv desired "rate ash-,zone h area by the pivotally connected frames 56, 57 one of which also is pivoted to relatively fixed supports, and said parts 7 are closed at 7 2, by the drum 39, or by the equivalent sprocket wheel flanges 42, to internally air-seal the rear grate turn 3, and said parts 7. are closed at 7 3, by the guides 49, to make an inner air-seal and to convey ashes forward.' and these guides also permitthe parts 7. to open at 7- L to dump said'ashes and then close them at 7 5, to catch and convey forward the 'good fuel sifting's. and

the guides also permit tilting of the parts 7 at 7 6. for dumping the recovered siftings `prior to their inal discharge at 52-1, at the furnace front.

Figs. 9 and 10 of the drawings showthat the inner air-seal of the rear grate ,turn` 3,1(

and the fuel siftings conveyers, may Ybe formed by transverse grate bars having' Figs'. land 2, but haying inner unhinged or frigid web portions preferably fforrned, by inner partsof the barrside plates 9,19, which are diverged suiliciently to causeftheni to abut or-quite `closely approach 'each other edgewise .to niake the" air-sealat the grate turn 3.4With this typeof grate bar may be used: an inner cylindrical drum 67 lfixed' lto the sprocket wheels 16, as in Fig. 9. With this druni the diverged inner'parts of each grate4 bar have two air-sealing places or` lines. of contact.. -1 ln Fig. 10, where the druin'GS is too 'sniallto allow thegiiate bars 'to touch it, each grate bar .has but two air sealingr places forv lines of contact at its plat-es 9, 9, with the adjoining bars, sub-l stantially as have the movable grate bar parte 7, when adjusted at 7 Q, in Fig.A 8.

In Fig. 9, .each gratel bar has four air-sealingzplaces or lines of contact, or two I.with

ladjoning bars and two withga drum, substantially as have the movable grate bar parts 7, when adjusted at.7-2, in Figs. 1

and 2. l y

Fig. 11 sufficiently vshows that` an. inner -aiiesealing druni 69 may be vplaced loosely within the rearagrate turn 3, between oppo- 'lower part of thel rear grate turn 3, without,

site disk-wheels 70, and'niay bear upon thrust blocks 71, which are fixed or bolted to `a non-revoluble shaftl 72. This permits up- -ward yielding `of the drum 69, with the lifting the heavy wheels 70, which may .turn

' .1' upon the sliaftfYQ'. Fig. 11 also shows that the diverged inner parts of transverse grate bar webs 'need not touch each other when they make radial contact with an .inner drum of ai'iylrind' at the rear grate turn 3,

l'lhe diverged i nner web parte of they grate #bars shown in Figs. 9, 10 and 11, forni cups 73, which atthe lower grate run .4, catch -1 good fuel Sittings' 52, which fall through the `upper grate run t2, and coiiif'ey them forward, and Fig. 9 shows how said Sittings' may pile upward inore lor less within the.

closed frontgrate turn" at 52 2, and roll backward into "the grate chamber 53.,.at 'the junction of thelo'wer grate run e andfront grate turn 1;. .As the grate continues its.

' movement its bar' fngei'fs diverge to produce aroundftlieni the larger openings 55,

through `which the recovered .siftings ,fall

from the chamber 53, as shown at 521, iny Fig. 9, and substantially as when the hinged web conveyers 7 of Figs.' 1 and 2 are used.

Ashes iiiay lodge in the cup conveyers 73 at rear 'portions of the grate, and these separated .cups will not catch at the lower O'ijate run 4, all the good fuel which sifts throi'ioli the upper grate run, and the siftings prior to ltheir final discharge areA piled up at 52-2, inside the abutting cups 73 at the if a* solid'air-sealing'and clinkergrindingA abutnient'QS'lbe used at the outer face thegrate.

closed front grate' turn. These objections .do not apply to the grate having inner inovallow clinker-holding' or 'warpedv `fuel carriers to` easily pass over-"any outer 'support for rear 'port-ions 'of the grate Without jamiiiingor stopping the grate. In Figs.`1, 2,

'8, `9, '10,12 and 13, 'the rear grate turn supf` porting. Wheels 1G are bored larger than the" shaft 18 to provide next' the 'shaft a'clearance space 74t, permitting the wheels'to swing 'upward and forward eccentrically. The outer abutment 28, or 28-.1,` is so located' that most of the weight' ofthe wheels 16, the gi'atetuin 3, and t-he inner druni when used, will fall upon the shaft while allowing said grate turn to bear heavily enough upon4 Vthe outer abutment to cause said abutment to grind all soft hot clinkers from the fueli' carrying faces 'of the grate and Wit-hout lifting said grate turn 3'. Should a hard -clinker 75 on the fuel carrierpass unground over the abutment it will, as shown in Figs.

so,A

2'and 9, simply raise one end 'of the grate turn 3, and the' inner druiii'lwhen used and one sprocket wheel 16, until' the clinker passes forward oit the abutment and the parte again resume normal rpositions shown in Figs. 1.aiidi10. "Passage of' an edgewisewarped grate bar over the outer 4abi'itinent would in like inannerI temporarily raise `,tlie grate turn 3. With the loose drum 69,' o

,Fig 11, a liardcliiikeror warped grate liar would lift the drum as 'it turns y upon the fixed thrust-blocks 71, there o ng sutlicient' lower clearance space at "i6 'between the wheels 70, and the sagged' grate bar couplings to permit this iiidojieiident diuin nioyenient. Vitl'i the grate bars having iii-v nei' inovable web portions v7, and lower .guides a9 operating them, the rear guide parts ,4Q-4L, and dfi- 2, are temporarily 'lifted troni the brackets 51, when the rean grate turn is lifted at one end by a hard' Iciinker "Z5 riding over either-outer abutment orI Qt-J, and whether the inner air-seal A ing d'i'uin be used or omitted..

Figs. 9 -10 ai.

swinging ash-zone dainpers are to be thin lplatee: Tf?, 4fixed one to the' top ot each of the swinging pivoted frames `51:2. 57. "When these frames are-successivelj k'a'ised andy ,lowered by Operating their glial -rods as .l 11 show that with urato Z i i bars liavino' ani-scalino- )arts or cu sn 'is .e .5. i later forming fuel Sittings conveyors, the

Lerares 4 5 above'described, the plates 77, swing with theframes and thus are made to close and open the spaces between said cups 73, to oontrol the draft through the grate ashezone. a Fig. 12 shows'an inner yielding air-sealing drum 73 and an outer concaved air-s aiing yand clinker--grinding abutment :9.3, with an endiess 'grate formed of series of longitudinallin'ks 79, hung at their side-lapped :te ends upon 'transverse pivot rods 80. These 'side-lapped link ends together form transversely ranging air-exclnding grate portions the longitudinal space between any tvvo of which is spanned or closed by the inner` its drum 73, and the outer abutment 2S, to form inner and outer air-seals at the grate turn 3. Figli? also shows one of a series of short swinging damper-plates 8l, which are pivoted at'82, to the opposite fixed side frames i9, Underlying pivoted frames 56, 57, are

to be adjusted to close and open said daniper-plates 81, at the grate ash-zone. A space-bridging damper-plate 83, is tlxed to the frame 56, between the rearniost swinging plate 81, and the drum 78.

"Figsl 1 3 and le, show that longitudinal links 84,"1vhich are pivoted at their thinner 'Sidelapped ends upon transverse rods 85, have' angular flangesi 86, which abut trans au 'versely and thus form a continuous trans verse ruel siftings conveyer 87. These con veyers 37,V act like the above named grate bar cups 73in abutting each other to form an inner air-seal at the rear grate turn Whether the inner drum 88, be used or omitted. Air supporting combustion passes up- Ward lbetween adjoining conveyers 87, and through small openings 89, between the link ends, asindicated by'the arrow, and the e0 good fuel Sittings are finally discharged through these openings when enlarged at the front grate turn l. Dainper-pla.tes'77, may be fixed to swinging frames 5G, 5T, to controi the draft through the ash-zone of this link grate. Grates made with either links- 79 or 84E,l also may rest upon a for- Wardlyl located flat abutment Z8-4, if an air-barrier plate be fitted inside the lower v'grate run 4, between the grate turn 3 and vsaid fiat abutment.

' In all 'the abovev described forms of the invention the opposite ends of the rear 'grate lturn arefair-sealed by opposite sides 19, 19 ofthe stoker frame, or by opposite furnace side Walls 90, 90, should said parts 19, be' omitted. Whether the 4transverse grate bars have movable inner parts 7, or haverigid inner air-sealing parts, it is ferred to make their fuel-carrying portions 5 "6, in two or three or more transversely red cast-iron sections held to and between io steel side plates 9, 9, by bolts 91, as town in Figs. 4 and?, t0 permit easy retal of any vinjured fuel-carrying part "',ffiithout stopping the grate.

rihere are special advantages in using fuel carriers formed as transverse grate bars having either movable or rigid'inner air-sealing portions which may also recover the fuel sift ngs, eoniuared with longitudinal llink 7o 'Such as shown in iiigs. l2 and i3. All

'es have manyjoints through .sable air leakage may occur the te. Transverse grate air ge and their outer ,fiiel-cariying parts also may be easily renewed without stopping the grate while linlr-grates usually are stopped to renew worn-outlinls, i l,Fi/Then the outer air-sealing abutment 28, 80 1s used under the internally air-sealed grate turn 3, and when ash-Zone dainpers at the grate run 2, may not be required, air-sealing of the interior of the grate to prevent passage of excessive volume of air from the in.- a5 taire 35i-e36, into the combustion chamber 3'?, is etteeted by the inner air-seals at the rear grate turn 3u Should this abutment Q8, be used with the grate turn inner air-seals and with required ash-zone dainpers, said dainpers then -would complete neeessaryvairsealing of interior of the grate. Should the tlat forward outer abutment 28--,l,` be used With inner air-seals at the grate turn 3, and should aslrzone dampers be omitted, necessary airseaiing'of the interior of the grate would be completed by the web plates 'i'. when closed at 7 3, in Fig. 8. Should this abutment QS-l, be used ivith the grate turn innerair-seals andV with ash-Zone dainpers, these darnpers and the closed web plates 7 3, or an equivalent air-barrier plate, then would complete necessary airsealing of the interior of the grate.

The terms imperforate7 and aire.v- 105 cluding and abut-l or abuttiug used in this specification are to be construed as including substantially imperforate air-excluding parts of the fuel carriers which either touch or quite closely approach each 11o other or the .inner drum or the outer fixed abutment to airseal rear portions of the grate in manner substantially as above described. Y

An inventor should disclose and'have pat- 115 ent protection tor the best or more complete devices and their combinations whichv may be used most advantageously, and he should also clearly specify and have patent protection for all novel sub-combinations of parts Which may be used with perhaps less advantage but Withgood practicalresults. lt is believed that all such combinations and sub-combinations of parts contributing more or less to the advantageous use of4 this in- 125 vention and specified in the -appended claims, will be clearly understood Without further detaileddescription. f

l clainras my invention l. A traveling stoker grate movable be- 'tween an air-intake and a combustion chamber and comprising fuel-carriers formed as transverse grate bars having air-excluding web portions, supports sustaining said grate bars at the rear grate turn, and a system of air-sealing `barriers coacting to cut oil the combustion chamber from the air-intake except at the fuel-combustion zone of the grate and including said grate bar Webs which abut each other edgewise at the grate turn and thereby form an inside air-seal at said turn, and a barrier opposing said 'Webs and air-sealing the outside of rear portions of the grate, and necessary barriers completing air-sealingof the interior of the grate.

2. A traveling stoker grate movable between an air-intake and a combustion chamber and comprising fuel-carriers formed as transverse grate bars having air-excluding web portions, supports sustaining said grate bars'atthe rearv grate turn7 and a system of air-sealing barriers coacting to cut off the combustion chamber from the airintake eX- cept at the fuel-combustion zone of the grate and including said grate bar Webs which abut each other edgewise at the grate turn vand also radially abut a port-ion of said grate turn supports and therebyform an inside air-seal at the grateturn, and a barrier opposing said webs and air-sealing the outside of rear portions of the grate, and necessary barriers completing air-sealing of the interior of the grate.

y8. A traveling stokergrate movable be tween an air-intake and a combustion cl1am.

ber and comprising fuel-carriers having transversely ranging air-excluding parts7 I supports sustaining the fuel-carriersat the said-transversely ranging parts of the fuelcarriers and air-sealing the outside of rear portions of the grate, and necessary barriers completing air-sealing of the interior of the grate.

4. A traveling Stoker grate movable between an air-intake and a combustion chamber'and comprisingl fuel-carriers formed as transverse grate bars having air-excludingv web portions, supports Sustaining said grate bars at the rear grate turn, and a system of air-sealing barriers coacting to cut off the combustion chamber fromfuthe air-intake except a'tthe fuel combustion' 'zone of thev grate and including said grate bar Webs which abut each other edgewise at the grate turn and thereby form an inside air-seal at said chainber fromvtlie air-intake except atl the fuel combustion zone of the grate and kin-V cluding said transversely ranging parts of the fuel-carriers Which radially abut a portion of said grate turn supports and thereby forni an inside` air-seal at the grate turn,`and an immovable nonfriable clinker-grinding abutmentopposing said transverselyranging parts of the fuel-carriers and air-sealing the outside of rear portions of the grate, and

necessary barriers complet-ing air-sealing of the interior of the grate.

6. A traveling stoker" grate movable be-l tween an air-intake and avcombustion chainber andcomprismg fuel-carriers formed -as transverse grate bars having air-excluding webportions, supports sustaining said grate bars at the rear grate turn, and a system of air-sealing barriers coacting` to cut oifthe combustion chamber from the air-intake except at the fuel combustion zone of the grate and including said grate bar Webs which radially abut a port-ion of said grate turn supports and thereby form an inside airseal at the grate turn, and an immovablel non friable clinker grinding abutment opposing said webs and air-sealing the outside of rear portions of the grate, and necessary barriers completing air-sealing of the interior of the grate. Y

7. A traveling Stoker grate movable between an air-,intake and a combustion chamber and comprising fuel-'carriers having transversely ranging air-excluding parts', supports sustaining the fuel-carriers at the rear grate turn, anda system of' air-sealing barriers coacting to cut off the combustion chamber from 'the air-intake excepty at the" fuel combustion zone ofthe grate and including said. transversely ranging parts of the fuel-carriers-Which abut each other edge# Wise at the grate turn and also radially abut a portion of said grate turn supports and thereby form an inside air-seal at the 'grate turn, and a nonfriable clinker-grinding abutment opposing said transversely ranging partsof the fuel-carriers and air-sealing; the outside of rear portions of the grate, and necessary barriers completing air-sealing of the interior of the grate.

8. A traveling Stoker vgrate movable be` tween an air-intake and a' combustion charm 'transversely ranging air-excluding parts, supports sustaining the fuel-carriers at the miams ber and comprising fuel-carriers formed as transyersergrate bars having air-excluding web portions, supports sustaining said grate barsat the rear grate turn, and a system of air-sealing barriersycoactmg to cut otf the rept and including said grate bar Webs Which abut each other edgewise at the grate turn and also radially abut a portion ov said grate turn supports and thereby form an inside air-seal at the grate turn, and a non- `friable clinker-grinding abutmentopposing saidwebs and air-sealing the outside of rear portions ofthe grate, and necessary barriers completing vair-sealing of the interior of the grate. .a

9.- .A traveling Stoker grate movable between an air-intake and a combustion chamber .and comprising fuel-carriers having `rear grate turn, and-a system of air-sealing barriers coacting to cutoff the combustion chamber from the air-intake except at the fuel combustion zone of the grate' and in-` cluding' said transversely ranging parts of *the fuel-carriers which abut each other e Ue- Awise at the grate turn and thereby form an j'inside air-seal atsaid turn, and an air-seal- .ing and clinker-grinding. abutment opposing the outer face lofthe grate turn for an are as long or longer than the space between any two adjacent transversely ranging air-sealiugfportions of the grate,y and necessary f barriers completing air-sealing of the interior *of the grate.

1Q.' A traveling` Stoker grate movable between an air-intake and a combustion chamber-` and comprising fuel-carriers formed as transverse grate. bars having air-excluding web portions., supports sustaining said grate bars at the rear grate turn, and a system of :air-sealing barriers coacting to cut Ioil the combustionchamber from the air-intake eX- cept at the fuel combustion zone of the grate y ,and vvincluding said grate bar Webs which i abut each other edgewise at the grate turn and thereby form an' inside air-seal at said 50 turinand an airfsealing andQclinker-grinding abutment opposing the outer face of the grate turn foran arc as long or longer than the, space between thewebls of any two adjoining grate bars, and necessary barriers completing air-sealing of the-,interior of the gratefv ll. ,A traveling Stoker grate movable between an 'air-intake and a combustion chamber yand 'comprising fuel-carriers having ,transversely ranging air-excluding H ,parts,

supports sustaining the fuelcarriers at the rear grate turn, and a system of air-sealing barri'ersooact-ing to cut of the combustion chamber r `from the air-intake except at the fuel combustion zone of the grate and iiiolnding said transversely ranging parts of the fuel-carriers which radially abut a tion of said grate-turn supports and there by form an inside air-seal at the grate turn, and an air-sealingr and clinke-r-grinding abutment opposing the outer tace of the t grate turn for an are as long or longer than the space between any two adjacent trans versely ranging air-sealing portions ot the grate, and necessary barriers completing air-sealing of the interior' of the grate.

l2. A traveling stolzer grate movable between an air-intalre and a combustion charnber and comprising fuel-carriers formed as transverse grate bars having air-excluding web portions, supports sustaining said grate bars at the rear grate turn, and a system of air-sealing barriers enacting to cut ofi" the combustion chamber from the air-intatte except at the fuel combustion Zone of the grate and including said grate bar webs which radially abut a portion ofsaid grate turn supports and thereby form an inside ain4 seal at the grate turin and an air-sealing and ciinker-grinding abutment opposing the outer tacey of the grate t-urnfor anvar-c as long or longer than the space between the webs of any two adjoi ing grate bars.J and necessary barriers completing airssealing 'of the interior of the grate'.

A 13. A traveling stolzer grate movable between an air-intake and a combustionrchamber and comprising tuehcarriers having transversely ranging air-excluding parts, supports sustaining the fuel-carriers at the rear grate turn, and a system of air-sealing barriers coasting to cut oil the combustion chamber from the air-intake except at the fuel combustion zone of the grate and including said transversely ranging-parts of the fuel-carrierswhich abut each other edgewise at the grate turn and also abut a portion of said grate turn supports and thereby form Aan inside air-seal at the grateturn, and an air-sealing and clinkerfgrinding abutment opposing the outer faceot the grate turn for an arc as long or longer than the space between any two adjacent transversely ranging air-sealing` portions of the grate, and necessary barriers completing ,air-sealing of the interior of the grate. l

14. A traveling Stoker grate movable between an air-intake and a combustion chamber and comprising fuel-carriers formed as transverse grate bars having air-excluding web portions, supports sustaining said grate bars at the rear grate turn, and a system of air-sealing'barriers coacting to cut oit the combustion chamber from the airintalre except. at the tuoi combustion sone ofthe grate and including said grate bar webs which abut each other edgewise at the grate turn andalso radially abut a portiono 'said rco .am turn supports and thereby forni an msiderair-seal at the grate turn, and an air- Sealing and clinker-grinding abutment opposing the outer face of t-he grate turn for.

an ar'c as long. oi' longer than the space betweenthe webs of any two adjoining grate ing parts of the coupled fuel-carriers andV air-sealing the outside of rear portions of the-grate.

16. A traveling stoker grate comprising fuel-carriers formed as transverse grate bars `having air-excluding' web portions, devices` flexibly coupling the grate bars together, supports --sustaining the coupled grate bars at t-he rear grate turn, said grate bars and their coupling devices and supports coacting to form an inside air-seal at t-he grate turn,

and an immovable non-friable clinkergrindingabutment opposing the webs of the coupled grate bars and air-sealing the outside of rear portions of the grate.

A17. A traveling stoker grate comprising fuel-carriers having inner conveyers adapted at the lower grate run toA catch unconsumed fuel siftings dropped from the upper grate run and to carry said sift-ings to and discharge thein at the front or outer portion of t-he grate. 18. A traveling stoker grate comprising fuel-carriers formed as transverse grate bars having inner conveyers adapted at the lower grate run to catch unconsumed fuel siftings dropped from'the upper grate run and to carry said siftings to and discharge them at the fr' nt or outer portion of the grate.

19. A traveling Stoker grate comprising fuel-carriers having outer portions forming a fuel bed at the upper grate run and havin-g' inner fuel siftings4 conveyers at the lower grate run, 4said outer portions of the fuelcarriers separating farther at the front grate turn to there permit final discharge of recovered fuel siftin s.

20. A traveling Stoker grate comprising "fuel-carriers formedas Atransverse grate bars having outer portions forminga fuel bed aty the upper grate run and 'havin-g iiiner fuel siftings conveyers at the-lower grate" runJ said outer portions of the grate b ars .separating farther at the lfront grate turn to there `permit final dischargev of recovered fuel siftings.

21. A travelingstoken grate fuel-carriers formed as transverse grate bars having webs provided at outer parts with yteeth oi fingers which intermesh at the u per grate run to there form a fuel bed, said webs having inner fuel siftings conveyers at the lower grate run,v the web teeth separating farther at the `front grate turn to there permit final discharge ofrecovered fuel siftings.

22. A- traveling-Stoker grate Vcomprising a series of fuel-carriers having inner fuel siftings conveyers which by edgewise contact with each other at the rear grate turn forman inside air-seal at said turn.

28. A traveling Stoker grate c omprising a series of fuel-carriers formed as transverse grate bars having inner fuel siftings conveyers ,which by edgewise contact with each other at the rear grate turn forman' inside air-seal at said turn.

24. A traveling` stoker grate comprising fuel-carriers having inner fuel siftings conveyers, and a drum or 'abutment arranged within the rear grate turn and with which said conveyers are in contact thereby formf ing an inside air-seal at said turn, and means air-sealing the outer face of the grate.

25. A traveling Stoker grate comprising fuel-carriers having inner fuel sift-ings conveyers, and a drum or abutment arran ed within the rear grate turn-and with which the conveyer of each fuel-carrier has two airsealingl contacts thereby forming an inside air-seal at said turn, and means air-sealing the outer face of the gra-te.A

' 26. A traveling stoker grate comprising fuel-carriers formed as transverse grate bars having inner fuel siftings" conveyers, and a drum or abutment arranged within the rear grate turn and withwhich said conveyers are in contact thereby forming an inside air-seal at said turn, and nieansair-sealing the outer face of the grate.

27. A traveling Stoker grate comprising fuel-carriers formed as transverse grate bars havinginner fuel siftings conveyers, and a ldrum or abutment arranged within the rear grate turn and with which the conveyer of ,each grate bar has two air-sealing contacts thereby forming an inside air-seal at said turn, and means air-sealing the outer face of the grate. y

28. An endless traveling Stoker grate comprising fuel-carriers formed asv transverse grate bars having an air-excluding main web portion provided with outer fuel sustaining parts` and anair-excluding inner auxiliary web plate or part hinged to said main web portion and coacting therewith in air-sealing functions., q V29. An endless traveling Stoker grate comprisn fuel-carriers each includi -an airexclu ing 'main web port-ion having router longitudinal fuel-sustaining teeth or fingers,

andan air-excluding inner auxiliary web` plate or part hinged to said toothed main --web portion and coacting therewith in airsealingfunctions. Y

`f1f 80. A traveling st'oker grate comprising -i'nel-carriers having an air-excluding main web portion provided with outer fuel-sustaining parts, and an air-excluding inner vauxiliary web plate or 'part hinged. to said main web portion and eoaeting therewith in air-sealing functions; the auxiliary web v'plate hinges comprising-one member having' closing and permitting opening of Said hinged .inner web plates at diHerent places alongjt-he course of travel of the grate.

32. An endless traveling Stoker grate comprising fuel-carriers each including an aireiolu'ding main web portion having outer feel-sustaining parts, and an air-excluding inner auxiliary web plate or part hinged to said mainweb portion and eoacting therewith in air-sealing functions, and guides operative beneath the upper grate run in front of the rear grate turn and there closing and permit-ting opening of said inner hinged web plates for regulating the draft throughthe grate ash-zone.

83. `A traveling Stoker grate comprising fuel-carriers having inner movable or hinged plates or parts, and guides around the rear lr'grate turn closing said movable plates edgewise to make an inside air-seal at said grate turn.

34. A traveling Stoker grate comprising yfuel-carriers having inner movable or hinged plates or parts7 and a corrugated drum within the rear grate turn closing Said mov- 9 able plates edgewise to makean inside airseal at said grate turn and providing ashreeeiving pockets between theV drum and the closed plates.

Q35. A traveling Stoker grate comprising fuelfoarriers having inner movable or hinged plates or parts, and guides arranged next the internally air-sealed grate turn atthe lower grate runand closing one or more of said inner movable plates edgewise directly in v frontof saidy grate ,turn at the lower grate g traveling Stoker grate comprising fuel-Carriers having inner movable or hinged tarn at the lower grate run closing one or more of-.said inner movable plates directly in front of said grate tur-n and permitting inward yielding of @linker-holding or warped fuel-carriers.

37. A traveling s'toker grate comprising fuel-carriers having inner movable or hinged plates or parts, and guides closing said movable plates at the grate turn and permitting opening of said plates at the .lower grate run in front of said grate turn for dumping ashes.

3S. A traveling Stoker' grate comprising fuel-carriers having inner movable or hinged plates or parts, and guides automatically closing said movable. plates at the lower grate run to cause said closed plates to receive and carry to the outer part of the grate unconsumed coal dropped from the fuel bed at the upper grate run.

39. A traveling Stoker grate comprising fuel-carriers having inner movable or hinged plates or parts, and guides automatically closing said movable plates hat the lower grate run to cause said closed plates to receive and carry to the outer partY of the grate unoonsumed coal dropped from the l fuel bed at the upper rate run, said guides permitting opening o the closed plates at or near the front grate turn for dumping the recovered fuel siftings.

40. A traveling Stoker grate comprising fuel-earrierseaoh having a web portion provided atits outerpart with longitudinal teeth or fingers which intermesh with the teeth of adjoining fuel-carriers to' form a fuel bed at the'upper grate run, each fuelcarrier web having an inner `movable or hinged plate or part, combined with guides l automatically closing said movable plates at the lower grate run to cause said closed plates to receive and convey to the .outer part of the grate unconsumed coal dropped from the fuel bed, said guides permitting opening of the closed plates at or near the front grate turn for dumping the recovered fuel siftings into chambers formed between the webs and teeth of adjoining fuel-carriers, said Siftings finally dischargingfrom said chambers through enlarging openings around the diverging outer teeth or fingers of the fuel-carriers atsaid front grate turn.

4l. A traveling Stoker grate comprising fuel-carriers having transversely ranging air-excluding parts, an yabutment air-sealing the inside of the rear grate turn, and a nonfriable elinker-grinding abutment air-sealing the outer face ofsaid grate turn for an aro spanning the space between any two adj aeent or following transversely ranging airexcluding portions of the grate, one of said abutments being yielding to permi passage of @linker-holding or warped fue -carriers between the two air-sealing abutments without. jamming the grate. i

42. 'A traveling stoker grate comprising fuel-carriers formed as transverse grate bars having air-excluding web portions, an abutment air-sealing the inside of the rear grate turn, and a non-friable clinker-grinding abutment air-sealing the outer face .of the grate turn for an arc spanning the Space between the webs of any two adjacent or following grate bars, one of said abutments being yielding to permit passage of clinkerholding or warped grate bars between the two air-sealing abutments without jamming the grate.

43. A traveling stoker grate having fuellcarriers, yand a sectional draft regulator comtwo or more pivotally connected frames or.I

parts one of which also is pivoted to relatively fixed supports, and devices adapted to independently and successively operate the pivotcd frames for closing'and pernntting opening of-said damper-plates.

45. A traveling stoker grate comprising fuel-carriers, supports having vertically yielding parts sustaining the fuel-carriers at the rear grate turn, and means sustaining rear portions ofthe grate at its outer face, whereby clinker-holding or warped fuelcarriers'riding over said outer grate sustaining means may yield with the grate turn supports to prevent jamming of the grate.

46. A traveling stoker grate comprising fuel-carriers formed as transverse grate bars, supports having vertically yielding parts sustaining said grate bars at the rear grate turn, and means sustaining the grate bars at the outer face of rear portions of the grate, whereby clinkcr-holding or Warped grate bars riding over said outer grate sustaining means may yield with the grate turn supports to prevent jamming of the grate.

47. A travelingstoker'grate comprising fuel-carriers, devices coupling said fuel-carriers together, supports having vertically yielding parts sustaining the fuel-carriers at the reargrate turn, and means sustaining irear portions ofthe grate at its outer face, 'whereby coupled clinker-holding or warped fuel-carriers riding oversaid louter grate sustaining means may yield with the grate turn supports to prevent jamming .of the grate. l

48. A traveling Stoker grate comprising vertically yielding parts sustaining the fuel-carriers at;

the rear grate turn, and a non-friable clinker-grinding abutment sustaining rear portions of the grate at its outer face.

. 50. A traveling stoker grate comprising fuel-carriers. formed as transverse grate bars, supports having vertically` yielding parts sustaining said'grate bars at the rear grate turn., and a non-friable clinker-grinding abutment sustaining rear portions of the grate at its outer face.

'51. A traveling Stoker grate -comprising fuel-carriers having transversely ranging air-excluding parts, supports including ver- 'tcally yielding parts sustaining the fuelcarriers at the rear grate turn, said yielding parts and the transversely ranging parts of the fuel-carriers coact-ing to-form an inside air-seal at the grate turn, and a barrier opposing said transversely ranging parts of the fuel-carriers and air-sealing a portion of the outer tace of the grate. y

52. A traveling Stoker grate comprising fuel-carriers formed astransverse grate'bars having air-excluding web portions, supports including vertically yielding parts sustaining said gratebars at the rear grate turn, said yielding parts and the'grate bar webs enacting to form an inside air-seal at the grate turm` and a barrier opposing the grate bar webs and air-sealing a portion of the outer face of the grate. l

53. A traveling Stoker" grate comprising fuel-carriers having transversely ranging air-excluding parts, supports including ver'- tically yielding parts sustaining the fuelcarriers at the rear grate turn, said yielding parts and the' transversely ranging parts'of the fuel-carriers coacting to form an inside air-seal at the grate turn, and a nonfriable clinker-grinding. abutment 4opposing said transversely ranging parts of the fuel-carsol riers and air-sealing the outer face of rear ing labutment opposingvthe gratte bar webs and air-sealing the outer tace ot rear portions of the grate.

-r55.'A*traveling*stoker grate comprising fuel-carriers having transversely Vranging air-excluding parts, supports including ver tically yield-ing, parts. sustainingk the fuelcarriers at the rear g ate turn, said yielding parts and the transversely ranging parts oi" the fuel-carriers enacting to torni an inside air-seal at the grate turn, and an air-sealing and clinker-grinding abutment opposing the outer face of the grate turn for an arc as long or longer than the space between any two adjoining transversely ranging air-sealing portions of the grate.

56. A traveling stoker grate comprising4 fuel-carriers formed as transverse grate bars having air-excluding web portions, supports including vertically yielding parts sustaining said grate bars at the rear grate turn, said yielding parts and the grate bar webs coacting to form an inside air-seal at the grat-e turn, and an air-sealing and clinker-grinding abutment opposing the outer tace of the grate turn for an arc as long or longer than' the space between the webs of any two ad- Joining grate bars.

57. A traveling Stoker grate comprising fuel-carriers having transversely ranging airexcluding parts, supports including a vertially yielding drum or abutment within the rear grate turn, said abutment and the transversely ranging parts of the fuel-carriers coacting to form an inside ainseal at the grate turn, and a barrier opposing said transversely ranging parts of the fuel-carriers and airy-sealing a portion of the outer face of the grate.

58. A traveling Stoker grate comprising fuel-carriers forme-d as transverse grate bars having air-excluding web portions, supports including a vertically yielding drum or abut- A ment within the rear grate turn, said abutment and the grate bar webs eoacting to form an inside air-seal at the-grate turn, and a barrier opposing the grate bar webs and air-sealing the outer face of rear portions of the grate. p

59. A ,traveling stoker grate comprising fuel-car1riers having transversely ranging air-excluding parts, supports including a vertically yielding drum or abutment within the rear grate turn,v said abutment and. the transversely ranging parts of the fuel-carriers coacting to form aninside air-seal at the grate turn, and a non-friable clinkergrinding abutment opposing said transversely ranging parts of the fuel-carriers and air-sealing the outer face of rear portions of the grate.

60. A traveling Stoker grate comprising' .abutment Within the rear grate turingj said abutment and thegrate'bar websjcoacting to form' an inside air-seal atthe ypxra'te turn, and a noni-friable clinker-grindi'ng abut- .ment opposing said grate barwebs and airseal-ing the outer face of rear' portions "of the grate.

6l. A traveling Stokerv grate comprising fuel carriers having transversely ranging air-excluding parts, supports including a vertically yielding drum or abutment within the rear grate turn, said the transverselyranging parts of the fuelcarriers coacting to form an inside air-seal at the grate turn, andan air-sealing and clinkergrinding abutment opposing the outer tace of the grate turn for an arc as long or longer than the space'between any two adjoining transversely ranging air-sealing portions of the grate.

62. A traveling Stoker grate comprising fuel-carriers formed as transverse grate bars having air-excluding web portions, supports including a vertically yielding drum or abutment within the rear grate turn, said abutment and the grate bar Webs coacting to lform an inside air-seal at the grate turn, andv an air-sealing and clinker-grinding abutment opposing the outer" 1face ci the grate turn for an arc as long or longer than the space between the webs of any two adjoining grate bars.

63. A traveling stoker grate comprising a series of fuel-carriers, interior supports for 4the rear grateturn including a loose drum or abutment held Within said turn and vertically movable therewith independently of other parts of said interior supports, and an outside support for the grate at or near said grate turn.

64.' A traveling stoker gratecomprising a series of fuel-carriers having transversely ranging air-excluding part-s, interior supports for the rear grate turn including a loose drum or abutment held within said turn and vertically movable therewith independently of other parts of said interior supports, said drum or abutment coacting with the transversely ranging parts of the fuel-carriers to form an inside air-seal at the grate turn, and an outside air-sealing support for the grate at or near said grate turn.

65. A traveling Stoker grate comprising a series of fuel-carriers, chains coupling said fuel-carr`iers together, interior supports for the rear grate turn including wheels over which run the fuel-carrier chains, and a loose drum or abutment held within the grate turn between the chain wheels and vertically movable independently of the Wheels, and an outside support for the grate at or near said grate turn.

66. A traveling Stoker grate comprising a series Vof fuel-carriers having transversely abutment and said fuel-carriers together, interiorsup orts the grate turn, and an outside air-sealing for the rear grate turn including w eelssupport for the grate at or near said grate 10 over which run the fuel-carrier chains, and a turn.

. loose drum or abutment held 'within the grate turn between the chain wheels andver- FRANK W HEDDEN' tcally movable independently of the wheels, Witnesses:

Said druml or abutment ooacting with the ALBERT J APPELL, fuel-carriers to form an inside air-seal at ALVIN K. GOODWIN. 

